late 14c., metaphisik, metafisik, "metaphysics," also "natural theology," from Old French metafisique and directly from Medieval Latin metaphysica (see metaphysics). This was the usual form of metaphysics until 16c.; it was somewhat revived 19c. under German influence.
"one versed in the science of metaphysics," mid-15c., perhaps from Old French methafisicien (14c., Modern French métaphysicien), or from metaphysic on the model of physician. In later colloquial use "one who practices the mind-cure," 1881.
"the science of the inward and essential nature of things," 1560s, plural of Middle English metaphisik, methaphesik (late 14c.), "branch of speculation which deals with the first causes of things," from Medieval Latin metaphysica, neuter plural of Medieval Greek (ta) metaphysika, from Greek ta meta ta physika "the (works) after the Physics," title of the 13 treatises which traditionally were arranged after those on physics and natural sciences in Aristotle's writings. See meta- + physics.
The name was given c.70 B.C.E. by Andronicus of Rhodes, and was a reference to the customary ordering of the books, but it was misinterpreted by Latin writers as meaning "the science of what is beyond the physical." The word originally was used in English in the singular; the plural form predominated after 17c., but singular made a comeback late 19c. in certain usages under German influence. From 17c. also sometimes "philosophy in general," especially "the philosophical study of the mind, psychology."
early 15c., metaphisicalle, "pertaining to metaphysics," from methaphesik (late 14c.) + -al, and in part from Medieval Latin metaphysicalis, from Medieval Latin metaphysica (see metaphysics). It came to be used more loosely in the sense of "abstract, speculative, apart from ordinary or practical modes of thought" (among others by Samuel Johnson, who applied it to certain 17c. poets, notably Donne and Cowley, who used "witty conceits" and abstruse imagery), and often had more or less a depreciative sense. Related: Metaphysically.